Tuesday, March 17, 2009

Professors at University of Oxford have undertaken a study, Ivy on Walls, to discover whether ivy acts bioprotectively or biodeterioratively with stone walls. Read about the study here.

I look forward to the results of this study because I am of the belief that ivy doesn't cause deterioration, it merely takes advantage of a deteriorating wall or sick tree. Its rootlets are not actual roots in the sense that they do not penetrate a surface in search of moisture or nutrients.

According to the above referenced book, Ivies, published in 1992, ivy is and always has been unfairly maligned. An experiment was conducted by Winchester College in the U.K., beginning in 1890, where half of the trees in an oak woodland were stripped of ivy every ten years and half were left covered with ivy growth. When the trees were felled in 1942, there was no difference in height, girth or average cubic content.

Ivy not only thrives where nothing else will, it provides shelter for birds and butterflies and food with some of the last nectar and berries going into winter. Ivy was the inspiration for poets and artists; it has a history of use as a medicinal herb and is the symbol of everlasting life.

In Delaware, it has been defined as an invasive, nuisance species so now people are ripping it out and putting in mulch which is so much better. Garden stores are advised against selling it and instead are requested to sell indigenous plants. I cannot argue that it is not indigenous to the U.S. but I'd much rather look at ivy in a dark corner of a shaded yard than a pile of mud or mulch.

While I was looking through the book for information, I found a four-leaf clover tucked in its pages. :-) I'll keep you posted on the study.

23 comments:

I'm conflicted about ivy. I love it in a pot, especially a varigated variety. As a ground cover, not so much.

Our former neighbor Virginia had the most perfect tree in her back yard, and the entire trunk, probably 20 feet tall or more, was covered with ivy, as was the ground around it. The problem was that it wouldn't stay there, and made it's way through and up our fence, which I didn't like.

Conversely, when I decorate for Christmas I always seem to use some good artificial ivy.

I love the ivy overtaking the sofa. It's so decadent and some other word I can't seem to get a grasp on...dammit! I have a succulent overtaking a stone bench in my backyard. I think I'm just going to let it do what it will. Oh...Big Love is one of my favorites too.

It's bad for painted brick walls... but other than that, I don't know. I love ivy in shady spots!! And I love that it grows so quickly! We used it in the tiny extremely shady courtyard off the back of my old condo, and it was wonderful to see growing up the (painted) brick wall. So much more interesting than just a wall. I also loved that it was green year round.

But you do have to keep it in check! And by keeping the pieces you cut back, you can start new plants!

I too have sometimes yes, others NO relationship with ivy. We had two ginormously long beds of it flanking the front approach. Each one about 40x3? And I had fits because when I see that much ivy I think "rat haven". What can I say? It's a thing of mine, just like palm trees are rat hotels.

I've removed it in stages over the years and I'm down to the last sections that are flanking the downward slope of the lawn. I've hesitated due to the difficulty and worried about creating a mini waterfall of clay and dirt BUT at the flower show in Philly I may have discovered a solution that could be perfect.

Braid the ivy into topiary "trees"!!! So, that's one of the projects for this spring. After I finish the dividing and transplanting and uh, stuff.

No mulching though. I know my neighbors roll their eyes at my winter beds but I just don't like the vast swaths of stinky mulch. I'm that neighbor who sweeps all the leaves into the beds and steps them down in. They make it all happy for the worms and in the spring I pull it all back to find all sorts of waiting sprouts.

There are many different kinds of ivy, with varying habits and characteristics. And the planting region matters, too.

In Southern California, we have an abundance of English ivy (Hedera helix). Not only is it ubiquitous and ugly, it is extremely invasive, smothers plants, kills trees, and harbors rats. Truly awful stuff. (If you live here, you know this.)

Check out the California Invasive Plant Council's website at:

http://www.cal-ipc.org/

On the other hand, Boston Ivy is lovely and very manageable in SoCal. Beautiful fall color and well mannered.

Let's hear it for Hedera helix aka English Ivy! It's a wonderful and versatile vine and I am in complete agreement -- I would much rather see ivy growing than mulch. The best thing about it is that it grows where other plants won't, plus it does not require irrigation and it isn't that hard to maintain -- but it does need to be kept at bay. Thumbs down to Delaware!

The stone house where we lived as small children was covered by virginia creeper. it was a perfect plant because it was all leafy and green in the summer, turned brilliant red in the fall and lost its leaves in the winter.

Scroll down a bit on this page and you will see a great example of gorgeous Virginia Creeper. This is a friend's castle in Wales. It was taken in the late fall when the Virginia Creeper was bright red, and I might add, just spectacular.

Anon: Just so you know, there are no rats in ivy out east. At least not in either of the two houses I've had.

And Boston ivy isn't evergreen which is one of the things I love about English ivy: green in winter.

David: I had a sycamore tree covered in it and the garage and some landscapers ripped it all down without asking. I was so upset! It's growing back on the tree but hasn't started back on the garage yet. I'll have to give it some help.

Lolo: If you live near Philly, you do not have rats in your ivy.

Did you go to this year's flower show? I don't recall seeing the braided topiary trees. I was hugely disappointed in the show.

HG, oh thank goodness on the no rats. It's a "thing" with me, a bit of holdover from growing up in Asia. Girl, the rats are the size of freaking dogs. We live in Berks Co. (or as we whisper "Jerks Contee") and the native vermin are many and do some serious damage on anything that is planted in their buffet.

The flower show, well we enjoyed it for the most part. It was something fun and family for me and the little girl to do. It was a mob of people though. I loved all the terrariums and orchids but we didn't spend much time in the landscaping displays. I'll check with my kid and see if she's got some pics of the braided ivy. I spent hours yesterday and braided four "trees", two more and I'll see how they do this year. Anything to avoid any more digging the fuckers up out of the clay beds.

We have a beautiful 60+ foot tall cedar tree in our yard. We had an arborist out last year, and he told us we needed to remove all the ivy growing in the shade of the tree (none was on the tree itself). He said the ivy robs surrounding vegetation of water, and that it prevents proper air circulation at the root level of the tree (in the soil? I'm not sure). Anyway, he said the tree was not thriving, partly as a result of the ivy.

In California, we have a year-round growing season so things can get really out of control. Think giant roaches and rats, and little shop of horrors vegetation. ha ha. The side of CA that no one ever thinks about. I don't think it would normally happen in this arid climate, but man has changed things with artificial irrigation, etc.

Ivy is just like bamboo. The wrong kind can be a nightmare. But there are all kinds, and there is a type suited to every locale.

I am a big fan of ivy - I think it is so beautiful when it grows on the side of brick homes. What a great idea for a post! It also made me inexplicably happy that you found a 4 leaf clover; my grandmother used to always search for 4 leaf clovers wherever we went, and once she found one in a field to the side of a road when we were lost in the English countryside.

I love ivy, and have a bunch of it in my backyard. My neighbor has been preaching the "invasive/non-native" thing at me for two years, but I refuse to remove it. We just try to control it by trimming it and keeping it off of the trees, etc. I'm glad to find this post-it eases my conscience!

I suppose I'll have to be in the minority. I live in the Pacific Northwest, and came to your blog via a google search for ways to kill the english ivy that is overtaking my yard. We bought the house last summer knowing that we'd have a bit of an ivy problem, and we've spent a year ripping it out and killing every little start before it gains even a toehold.

Ivy not only kills trees, but it crowds out native plant species, turning whole areas into ivy deserts. We're trying to nurture some native woodland plants such as sorrel and salal in the shade of our big cedar, as well as some rare and local ferns. We've had some success, but only because we're on a vendetta against ivy.

So please don't plant it or cultivate it. You'll regret it, and the fragile native plants of your area will too.